Testing device



Nov. 6, 1928. l ,f 1,690,269

f w. T. BOOTH ET AL.

TESTING DEVICE Filed Oct. 21, 1924 MHH.

1"...falaaV Nav. '6,' 192e,` ,1

uNigrizo`:STArust` y WILLIAM T. AisooTn, or ELUs'HiNG, AND ARTHUR o. .MAGRATIL oE NEW Dour, NEW yeux. AssierNoEswTol WESTERN ELECTRIC/COMPANY,,iNcoRPoRATEn or NEW (YORK, N, Y., A` GORI?ORATIONtFv NEW YORK.

TESTING DEVICE.

` Application led Octoberr21, 1924. Seriall No 745,030.

Y This invention relates ,to a testing device, and more 'specifically to a tiinemeasuring device which is particularly well adaptedfor use for testing lthe speed of impulsev senders 5 orcalling dials ofthe type generally used t for controlling the operation of switchesin automatic telephone exchanges, such as sef lectors and connector switches and the like. These dials are adj ustedto send impulses over 10 the telephone line tocontrolthe setting of the i si`1vit(`:hes,`a1 1d` any variation in the speed of y these dials `may cause the switch to establish wrongtelephone connections. v

The object of this invention is to provide la testing device whichwill be simple',fefiicient,

Vcheap to manufacture and wherein the speed of thedial tobe tested is readily indicated.`

In accordance-with this invention, a'vdialy .i tester `is provided'wherein a gravity pendulumand ajcontactingl pointer are heldin a starting position by an electromagnet, thev energization of which is controlledfby the iml l pulse sender to be tested;l The impulse sender i lin. being operated, releases the pendulum. f` The pointer is `held and carried'by the pendulum while the sender is Aoperating through the energizationof a magnet carried by the pendulum.` Instantly upon the termination of the operation of the sender, the pointer is Y released and springs Vinto y engagement with one .of a numberof "segments'disposed on the y'frame `of the instrument,1the particular segfment engaged depending'on' the speed of the dial. `lhependulum swings freelyv after the 35 pointeris released.;

'lhesegments referredito are electrical conv ,y

tactsc'onne'c'ted to annunciators adapted for visually or otherwiseindicating the speed of the sender. A third magnet or solenoid mayL v 40 beV employed tores'et the pendlum and pointer,

this solenoidbeing operated by a circuit closedl by the actuationof akey to move an arm which engages the pendulum and/pointer to reset them.k In'orderto control'the release of to transmitlimpulses,and 4on its'i'irst step Opens the start magnet circuit, andon receipt .ofthe last impulse from they senderV opens thecircuit of thejpointer control maghetto i t allow the pointer tofspringintocontact with the segment it happens to be opposite atthat moment.

Whenthekey referredvto is operated,wthe

release lmagnetof the stepping switch is operated to withdraw the holding pawl to allow a retracting spring to restore `the `stepping switch to normal, in which. position it recloses the starty magnet and hold'magnet circuits so that when the pendulum and pointer reach the start position under controlof the solenoidvreferredto, these magnets are energized and hold the pendulum vand pointer in their normal. positions lready for another measuring operation; .l 1 V Other features` will appear from thejfol `lowing description takenin connection with Vthe accompanying drawing, which shows the preferred embodiment -of this inventionin which measuring device.' Fig. 2 is a detail view of the pendulum showingfthe resilient arm in con tacting relation with an associated segment.

Figs and'tare partial views of the fulcruin of the pendulum showing thecontacting and resetting arms in position on their respectivel supportsand Fig.` 5 is al partial view ofthe. PlaterllOlCling the annunciators.

Fig., l is a front assembly view of the time `The time measuring device of this invention i generally I consists ofaframe Q10 which is provided with' a laterally extendingv bracket 11- better seen in Fig. This bracket is provided Vwith two coaXiallydisposedV shaped v groovesin which the prismsS and 9 forming the vfulcruin of a compound pendulum rest as shown in Figs. 3 and 4c. 'These two prism" shaped portions 8 and 9 are preferably integrally formed with a bracket 14 inwhicli the' two parallelly disposed rodsv 12fand Vl?) are mounted and heldr securely thereon by means of screws l5'. lThependulum weights 16 and 17 are mounted onthedownward extending portions of rods lZand 13 which are held in spaced relation at thispoiiitlby means of a bracket QOhe'ld on the rods' by means of'screws 18 and 19.

Bracket 2O cariiesa magnet 2l which is disy posed,inoperablev relation with a resilientr conducting arm QZprovided `witha contact point 23' integrally formed with a hook por-V tion 24. `Arm 22isvlooselyA mounted von pivotalaxisof the pendulum.

pivot 25 which-is disposed coaXially the 105 On the upward extending portions of rods 12 and 18 and disposed above the pivotal points of the pendulum, are loosely mounted the compensating weights 26 and 27. rlhese weights ai'e secured to a yoke 28 which carries a screw 29 the end of which rests on a bearing 30 mounted on the bracket 14. This screw is provided for i'aising or lowering the weights 26 and 27 for adjusting the oscillating period of the pendulum in a manner well known in the art. A counter-nut 3l is provided iorlocking screw 29 and the weights 26 and 27 carried thereby in adjusted position.

At a suitable distance below the pivotal point of the pendulum and supported by the rods 12 and 13 there is provided an adjustable weight 4() adapted to be moved laterally along the screw 41 for moving the center of gravity of the pendulum and the magnet 21 in alignment with the pointer 42 disposed in the central portions of sector 30. rlhe weight is held in adjusted position on the screw 41 by means of counter-nuts 43 and 44. The screw 41 is rigidly fastened on brackets 45 and 46 which are held on the rods 12 and 13 by any suitable fastening means.

The sector 30 is preferably made of insulating material and is securely held on the lower portion of the frame 10 by means of screws 47. This sector is provided with a plurality of contacting segments 31, 82, 33, 34, 35, 236, 37, 38 and 39 disposed in a plane parallel to the path described by the pendulum and contacting arm 22.

The contacting segments 31, 32, 33,etc., are electrically connected with their respectively associated annunciators 48, 49, 50, 51, 52, 53, 54, and 56 which cooperate with the contacting arm 22 for indicating the speed of the impulse sender in a manner that will be hereinafter described. Y v

@n the front portion of bracket 11 there is pivotally mounted a resetting arm 57 shown in Figs. 1, 2 and 3, which is attached to the plunger 58 of electromagnet 59 by means of a link 60.

Opposite magnet 59 there is disposed an air-dash pot 61 having a rod 62 connected to the resetting arm 57 by means of link 63. A springl 64 hooked on the adjusting screw 65 and on the upward extending portion 66 of resetting arm 57 is provided for returning the plunger 0S, rod 62 and the resetting lever 57 connected thereto in normal non-operated position against the contact springs 72, the function of which will be hereinafter described.

The resetting arm 57 carries an adjustable stop 67 adapted to engage the bracket 46 for moving the pendulum and the bracket 45 carried thereby in starting position against the core of a start magnet'68. On the downward extending end portion of resetting arm 57 there is provided a catch member 69 adapted to engage and nieve the contacting arm 22 and the pole piece 21 carried thereby in alignment with the core of magnet 21 with which it is associated. An adjustable stop 7 4 mounted on the frame 10 is adapted for limiting the movement of the arm 57.

'lhe resetting arm 57 carries a spring op* erating member 70 which extends laterally therefrom in operable relation with the pairs of contact springs 72 and 7 3 respectively. The springs 72 are adapted to close the circuit of an aniiunciator (200) which may be provided for indicating that the resetting arm 57 is in normal non-operated position thereby preventing the operation of the impulse sender to be tested while this resetting lever nieves the pendulum and the contacting arm in normal or starting position.

'lhe contact spring 7 3 cooperates with the stop 74 for limiting the movement of arm 57 and to open the operating circuit of magnet 59 when the pendulum and the contacting arm 22 are in normal starting position against the core of magnet 68 as shown by the dotted lines in Fig. 1.

rlhe operation of the time measuring device and its operating circuits are as follows:

The pendulum is normally held in starting position by means of electromagnet 68 which onei'gizes in a circuit from grounded battery, the coil of magnet 68, conductor 75, segment 79 and brush 76 of a stepping switch A to ground. The operating magnet OM of switch A is energized in a circuit from grounded battery, the coil of the stepping magnet, conductor 77, the impulse springs of the impulse sender to be tested to ground. Upon the operation of the sender the wiper 7 6 moved ten steps in the position indicat ed by the dotted line. Upon the first movement of wiper 76 from normal, the operating circuit of magnet 68 is opened at contact 7 S). This magnet releases the pendulum and the contacting arm 22, held in operable relation therewith through the energizatioi'i of electromagnet 21, is carried during this measuring period in a path adjacent the contacting segments 31-82, etc. At the end of the pulsing operation the wiper 76 is moved clear of segment 8O as shown by the dotted line, tluis causing the deenergization of magnet 21 which permits the arm 22 to s ring into contact with one of its associate segments 31--32, etc. under the medium of its own tension.

Magnet 21 was energized in a circuit from ground, wiper 76 of the stepping switch A. conducting segment 80, conductor 81, close/d contact springs S2 and 88, conductor 84, the winding of magnet 21, conductor to bat tery and ground. It is to be noted that the contacting segment with which the arm 22 may contact at the end of each pulsing operation depends solely upon the speed at which the impulses are sent through the stepping switch A with respect to the time element Uli lll)

lil)

. which is generally adjustedto V'move from its starting point tothe segment 31 iny one i seconds time.

Upon the Contact of arm 22 With one of its associated segments Jfor example, as shown at 86 in ig. l,\the circuit of annunciator 55 .is closed throughgijound, the metallic portion of contact arm 22segment 38, conductor 87, the Winding of magnet to battery and ground. kThis magnet attracts its armaturey and moves. the shutter. 8 8 carried thereby from the front portion of its associated magnet on which 'the number of impulses per`second particular to this segment is visually indicated. c Y

The resetting of the switch A, the pendu- `lum and the contacting' arm carried thereby is ei'ected simultaneously through tlierdepression of key 89 which closes a circuit forV 20.`

electromagnet 59 through ground, spring 90, conductor 91closed contact spring 78, conductor 92, Winding( ofmagnet 59 to battery and ground. v The magnet 59 energizes in the circuit and `operates the armi57 against the resistance of the air-dash pot 61 and retractf inglspring 64. The stop 67 carried by this resetting arm in its path engages theA bracket. 46 and the catch 69 engages the`liook 24 of, arm 22 or moving the pendulum and the con.

tacting arm in normal nonoperated as shown by the dotted line in Fig. l. y v

The movement of spring 94E, arranged to be moved simultaneously with key 89, closes aA circuit for magnet 93 through ground, springs 94 and 95,` conductor 96, the Winding positio-n of magnet 93 to batteryand ground. This' magnet energizes and operates the paivl 9710i ythe stepping device against the resistance of spring 101 to permit the Wiper 6 to return to normal non-operated posi-tion `under the tension of a spiral spring 98 thus closing the circuitsy ofmagnets 21and 68 which remain energized in these circuits for holding the pendulum and the arm 22 in starting position.

4Spring 82 `normally in contact with spring 83 is disposed in operative relationvvithtlie insulating memberlOO carried by the compensating Weight 26 and is adapted for openingy the circuit-of magnet '2l to prevent the contacting arm 22 from passing beyond the l outermost disposed segment 3l. Y

' What is claimedgis: l;` VA dial tester consisting ofa gravity pendulum, a magnet for holding the pendulum oil-center, a pointer, a magnet for holding the ypointer to thependulum, an impulse sender,

. and circuits controlled bysaid impulse sender Y for successively deenergizingsaid.magnets at y the beginning` and termination of a set of impulses transmitted bythe sender.

2., A dial tester consisting of ka gravity pendulum, a magnet for holding they' pendulum off-center, a contact. arm, ainagnet on the pendulum for holding the arm to the pendulum, an impulse sender, circuits controlled by said senderfor successively deenergizing said magnets at Vthe beginning and termination of a set of impulses transmitted by said sender, a row of contacts one of Which the contact arm engages When released, and signaldevices conneotedtothe respective contaeter-for indicating the elapsed time.

3. In atestingdevice, an impulse sender, a pendulum, a contacting arm pivoted on said pendulum, an armature carried by said pendulum, a magnet cooperating with said arma- Y ture for holding said pendulum and said arm in starting position, a magnet carried by said pendulum for operatively holding said arm to saidvpendulum, a switching device oper` able in response tothe movement of said sender for releasing the pendulum from the first mentioned magnet upon the lirst impulse j from the sender, means operable upon the lastv .impulse from the sender for releasing the arm iiom the last mentioned magnet for VYindicating the speedof said sender, Vand means for returning said pendulum and said one of said magnets at the beginning of the impulses iand the deenergization ofthe secjV ond mentioned magnet at a point depending upon the speed of said sender for causing the operation of one of said devices forindicating the speedl of said sender,a circuit for each of said magnets, and a solenoid for restoring the pendulum and member to normal position. y

5. `In a testing device, the combination of an impulse sender, a normally non-operating time element,.electromagnetic means for holding said element instarting position, a j pivoted conducting member, a magnet oper` vatively connectingjsaid member With said element, contacts positioned in a path pa'raln lel to the movement of said member, indicat@ ing devices operatively connected to said contacts, and a stepping mechanism for releasing ythe time element from the electromagnetic means at the beginning of the setof impulses,

and releasing the conducting member from the element at the end of the set of impulses to operate one of said devices upon'the en-v .gagement V`of said member With oneof said contacts.-

In Witness'whereoi, Wehereunto subscribe our names this 16th day of October, A. D.

i924.` WILLIAM' T. BOOTH.

ARTHUR` o. MAGRATH. 

